1840 The managed disk has bad blocks.

Explanation

These errors are virtual medium errors, which are created when you copy a volume where the source has medium errors. During data moves or duplication, such as during a FlashCopy process, an attempt is made to move medium errors; to achieve this, virtual medium errors called bad blocks are created. After a bad block is created, no attempt is made to read the underlying data, as there is no guarantee that the old data still exists after the bad block is created. Therefore, it is possible to have bad blocks, and thus medium errors, reported on a target volume without any medium errors on the underlying storage. The bad block records are removed when the data is overwritten by a host.